Can changes be made to segments in an existing accounting flexfield structure?
No. This will cause data inconsistencies and data corruption. Development and Support do not support changes to the accounting flexfield. Changing your flexfield definition once you have used it to acquire data can cause serious inconsistencies with existing data, which could cause data corruption. See the Oracle Applications Flexfields Guide, Release 11i, page 2-19, and the Oracle Applications Flexfields Guide, Release 11, page 2-18 for more information.